1. Field of the Invention
This invention relates to a method of manufacturing a flat friction ring which consists of a supporting ring and a friction lining provided on at least one side of the supporting ring and forming, at least approximately radial oil grooves, which friction lining is first cut out of a friction lining web including slits extending from at least one circumferential side for forming the future oil grooves, and is then glued onto the supporting ring.
2. Description of the Prior Art
For manufacturing flat friction rings it is known (EP 0 305 582 A1) to punch out the friction lining from a friction lining web as a self-contained ring with slits forming the future oil grooves, which friction lining web is made of an organic friction material as in paper making, and to glue this friction lining ring onto the supporting ring. Cutting out a self-contained friction lining ring, which already includes the slits for the future oil grooves, ensures an easy and inexpensive manufacture, but due to the annular shape of the friction linings, there is a high waste of material of the friction lining web, so that the material utilization is unsatisfactory. If, according to another known manufacturing method (EP 0 583 516 A1), the friction lining is composed of single friction lining sectors, which are cut off from a strip of friction lining and are glued onto the supporting ring in a way spaced from each other so as to obtain radial oil grooves between adjacent friction lining sectors, a good material utilization regarding the friction lining is achieved, which has, however, the considerable disadvantage of an expensive and time-consuming manufacture, because the individual non-coherent friction lining sectors must be positioned accordingly before they are glued onto the supporting ring.
It is therefore the object underlying the invention to improve a method of manufacturing a flat friction ring of the kind described herein above, so that a simple, quick and inexpensive handling of the friction lining can be combined with a good utilization of material.